To meet the demand for wireless data traffic having increased since deployment of 4th generation (4G) communication systems, efforts have been made to develop an improved 5th generation (5G) or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post Long Term Evolution (LTE) System’.
The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 28 GHz or 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems.
In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like.
In the 5G system, Hybrid frequency shift keying (FSK) and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
Conventionally, mostly, a method for controlling transmission is to focus on the maximization of a throughput based on Transmission Control Protocol/Internet Protocol (TCP/IP). Particularly, as the TCP/IP widely used in a wired data communication network is extended to a wireless network, there occurs a problem of serious degradation of transmission performance in a TCP connection which does not appear in a wired network. That is, since it is difficult to achieve a high throughput due to the mobility of a user equipment and a time-varying characteristic of a wireless channel, various methods have been proposed for accurately estimating a state of the wireless channel or rapidly recovering from a low throughput. However, techniques for maximizing a throughput cause an unnecessarily excessive transmission delay by injecting exceedingly many packets into a network, and the unnecessarily excessive transmission delay is a main cause which makes it difficult to provide a service sensitive to a transmission delay in a cellular network environment.
Since the prior art cannot properly reflect a change in a Round-Trip Time (RTT) depending on a state change of a wireless channel, although a situation of the wireless channel becomes worse, there may occur a problem of the degradation of transmission performance in the RTT-based prior art which depends on a case where a minimum RTT value still maintains a small value, the problem that it is difficult to distribute a fair throughput when a base station directly receives data from multiple servers, or the problem that it is impossible to make a differentiation between throughputs which is based on weights among multiple services with respect to one user equipment.
Currently, a requirement for low latency performance for a new 5G service is increasing, and there is a need for a solution in terms of a transmission control protocol for ensuring low latency performance. Also, currently, since a mismatch between design purposes for a TCP and a cellular network deepens a queueing delay of the cellular network, there is a need for a throughput control technique for solving this problem.